Implying legato when playing pizz sounds hard.
All of the points you made were good, but after having these in my life in one way or another for over 10 years this aspect has been the most important technical challenge. Along with intonation fine tuning, it's also been the single greatest growth area that has resulted from studying the suites. Some of the things I've learned about legato:
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Actual legato playing ( smooth connections with no new attacks) pizz is very limited compared to arco; with the bow you can connect notes together under with one stroke, but with pizz you basically only have hammers and pulls, both of which are limited to one or two notes after the attack.
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Implied legato playing (making lyrical connections while still attacking each note, as in pianistic legato) is more about shades of touch, right/left hand connection, and mental phrasing of the music. Thinking like a pianist helps, since in piano scores you are actually articulating each note on a percussion instrument, yet the phrase may be written as a slur covering multiple entire measures.
* When a string has to be re-articulated, there will always technically be a break in the line, as there would be with a change in bow direction; but based not he way we hear, if the left hand makes connections and the right hand stroke has enough velocity, that break can be short enough that the ear/brain still perceives the line as "connected". This is especially true if the line has an overall dynamic contour that the ear is following.
Very nerdy but interesting stuff!